1
IMSA Signal Technician Level 1 End of Chapter
Questions With 100% Correct Answers
SECTION 1: TRAFFIC SIGNAL FUNDAMENTALS (12 Questions)
Q1: According to NEMA TS-2 standard, which phase numbers typically represent the opposing
through movements on a dual-ring eight-phase controller?
• A. Phases 1 and 5
• B. Phases 2 and 6 [CORRECT]
• C. Phases 3 and 7
• D. Phases 4 and 8
Correct Answer: B
Rationale: Correct because in NEMA eight-phase dual-ring controllers, phases 2 and 6 are
opposing through movements; phases 1 and 5 are opposing left turns on the same street.
Q2: In a dual-ring controller, a barrier is defined as:
• A. A physical wall inside the controller cabinet
• B. A time separation between rings that forces phases on one side to complete before
crossing [CORRECT]
• C. A conflict between two opposing left-turn movements
• D. The maximum allowable green time for any phase
Correct Answer: B
Rationale: Correct because a barrier is a time separation point in dual-ring operation that
prevents phases on opposite sides of the barrier from operating simultaneously, ensuring
conflicting movements do not receive green concurrently.
,2
Q3: A traffic signal is operating in coordinated mode with a 120-second cycle length. Phase 2
has a split of 40 seconds. This means:
• A. Phase 2 will always display green for exactly 40 seconds regardless of demand
• B. Phase 2 is allocated a maximum of 40 seconds of green time within the cycle
[CORRECT]
• C. Phase 2 has a 40-second yellow clearance interval
• D. The offset between intersections is 40 seconds
Correct Answer: B
Rationale: Correct because split refers to the time allocation (percentage or seconds) assigned
to a phase within the cycle length; phase 2 receives up to 40 seconds of green time before
force-off occurs in coordinated operation.
Q4: In an actuated signal controller, "gap out" occurs when:
• A. The phase reaches its maximum green time
• B. The time between successive vehicle detections exceeds the passage time setting
[CORRECT]
• C. The controller loses power and restarts
• D. A pedestrian push button is activated
Correct Answer: B
Rationale: Correct because gap out terminates a phase when the gap between detected
vehicles exceeds the programmed passage time, indicating insufficient demand to justify
continued green.
Q5: Which of the following best describes "offset" in coordinated signal systems?
• A. The physical distance between two signalized intersections
,3
• B. The time relationship between the start of green at coordinated intersections
[CORRECT]
• C. The difference in cycle lengths between master and local controllers
• D. The amount of yellow clearance time programmed
Correct Answer: B
Rationale: Correct because offset is the time difference between the start of the coordinated
phase (typically main street green) at one intersection relative to another, designed to create
progressive traffic flow.
Q6: A signal controller is programmed with recall on Phase 2. This means:
• A. Phase 2 will skip its green interval and go directly to yellow
• B. Phase 2 will receive a continuous call and be served every cycle [CORRECT]
• C. Phase 2 will only operate during peak hours
• D. Phase 2 will flash red continuously
Correct Answer: B
Rationale: Correct because recall places a continuous call on a phase, ensuring it is served
every cycle regardless of detection, commonly used for coordinated phases or pedestrian
phases.
Q7: In NEMA dual-ring operation, which phase pair represents opposing left turns on the cross
street?
• A. Phases 1 and 5
• B. Phases 2 and 6
• C. Phases 3 and 7 [CORRECT]
• D. Phases 4 and 8
Correct Answer: C
, 4
Rationale: Correct because in standard NEMA eight-phase numbering, phases 3 and 7 are
opposing left turns on the cross street (near-side left turns), while phases 4 and 8 are far-side
left turns.
Q8: A pre-timed signal controller differs from an actuated controller in that:
• A. Pre-timed controllers use detection while actuated controllers do not
• B. Pre-timed controllers operate on a fixed cycle length regardless of demand
[CORRECT]
• C. Pre-timed controllers can only operate two phases
• D. Pre-timed controllers require a master controller
Correct Answer: B
Rationale: Correct because pre-timed signals operate on predetermined cycle lengths and
phase sequences without responding to real-time vehicle detection, making them less efficient
than actuated systems.
Q9: During coordinated operation, a "force off" occurs when:
• A. The conflict monitor detects a fault
• B. A phase is terminated at a fixed time point in the cycle regardless of demand
[CORRECT]
• C. The controller switches from actuated to pre-timed mode
• D. The flasher unit activates automatically
Correct Answer: B
Rationale: Correct because force off is a coordinated timing parameter that terminates a phase
at a specific point in the cycle to maintain the overall cycle length and offset relationship.
IMSA Signal Technician Level 1 End of Chapter
Questions With 100% Correct Answers
SECTION 1: TRAFFIC SIGNAL FUNDAMENTALS (12 Questions)
Q1: According to NEMA TS-2 standard, which phase numbers typically represent the opposing
through movements on a dual-ring eight-phase controller?
• A. Phases 1 and 5
• B. Phases 2 and 6 [CORRECT]
• C. Phases 3 and 7
• D. Phases 4 and 8
Correct Answer: B
Rationale: Correct because in NEMA eight-phase dual-ring controllers, phases 2 and 6 are
opposing through movements; phases 1 and 5 are opposing left turns on the same street.
Q2: In a dual-ring controller, a barrier is defined as:
• A. A physical wall inside the controller cabinet
• B. A time separation between rings that forces phases on one side to complete before
crossing [CORRECT]
• C. A conflict between two opposing left-turn movements
• D. The maximum allowable green time for any phase
Correct Answer: B
Rationale: Correct because a barrier is a time separation point in dual-ring operation that
prevents phases on opposite sides of the barrier from operating simultaneously, ensuring
conflicting movements do not receive green concurrently.
,2
Q3: A traffic signal is operating in coordinated mode with a 120-second cycle length. Phase 2
has a split of 40 seconds. This means:
• A. Phase 2 will always display green for exactly 40 seconds regardless of demand
• B. Phase 2 is allocated a maximum of 40 seconds of green time within the cycle
[CORRECT]
• C. Phase 2 has a 40-second yellow clearance interval
• D. The offset between intersections is 40 seconds
Correct Answer: B
Rationale: Correct because split refers to the time allocation (percentage or seconds) assigned
to a phase within the cycle length; phase 2 receives up to 40 seconds of green time before
force-off occurs in coordinated operation.
Q4: In an actuated signal controller, "gap out" occurs when:
• A. The phase reaches its maximum green time
• B. The time between successive vehicle detections exceeds the passage time setting
[CORRECT]
• C. The controller loses power and restarts
• D. A pedestrian push button is activated
Correct Answer: B
Rationale: Correct because gap out terminates a phase when the gap between detected
vehicles exceeds the programmed passage time, indicating insufficient demand to justify
continued green.
Q5: Which of the following best describes "offset" in coordinated signal systems?
• A. The physical distance between two signalized intersections
,3
• B. The time relationship between the start of green at coordinated intersections
[CORRECT]
• C. The difference in cycle lengths between master and local controllers
• D. The amount of yellow clearance time programmed
Correct Answer: B
Rationale: Correct because offset is the time difference between the start of the coordinated
phase (typically main street green) at one intersection relative to another, designed to create
progressive traffic flow.
Q6: A signal controller is programmed with recall on Phase 2. This means:
• A. Phase 2 will skip its green interval and go directly to yellow
• B. Phase 2 will receive a continuous call and be served every cycle [CORRECT]
• C. Phase 2 will only operate during peak hours
• D. Phase 2 will flash red continuously
Correct Answer: B
Rationale: Correct because recall places a continuous call on a phase, ensuring it is served
every cycle regardless of detection, commonly used for coordinated phases or pedestrian
phases.
Q7: In NEMA dual-ring operation, which phase pair represents opposing left turns on the cross
street?
• A. Phases 1 and 5
• B. Phases 2 and 6
• C. Phases 3 and 7 [CORRECT]
• D. Phases 4 and 8
Correct Answer: C
, 4
Rationale: Correct because in standard NEMA eight-phase numbering, phases 3 and 7 are
opposing left turns on the cross street (near-side left turns), while phases 4 and 8 are far-side
left turns.
Q8: A pre-timed signal controller differs from an actuated controller in that:
• A. Pre-timed controllers use detection while actuated controllers do not
• B. Pre-timed controllers operate on a fixed cycle length regardless of demand
[CORRECT]
• C. Pre-timed controllers can only operate two phases
• D. Pre-timed controllers require a master controller
Correct Answer: B
Rationale: Correct because pre-timed signals operate on predetermined cycle lengths and
phase sequences without responding to real-time vehicle detection, making them less efficient
than actuated systems.
Q9: During coordinated operation, a "force off" occurs when:
• A. The conflict monitor detects a fault
• B. A phase is terminated at a fixed time point in the cycle regardless of demand
[CORRECT]
• C. The controller switches from actuated to pre-timed mode
• D. The flasher unit activates automatically
Correct Answer: B
Rationale: Correct because force off is a coordinated timing parameter that terminates a phase
at a specific point in the cycle to maintain the overall cycle length and offset relationship.
